I started to roll out puppet to manage our servers at work and have to say I am impressed. It really changed the way I think about managing systems and is so much cleaner and easier to understand than the ‘traditional’ way.
Just being able to automate often repeated steps like enabling LDAP access or distributing config files makes puppet worthwhile. That the configuration is self documenting and versioned makes puppet priceless.
I will not post a tutorial here, just links to a few I found useful:

If you have to manage more than two or three servers, read up on puppet and consider using it (or any other configuration management tool).  It will be worth the time learning it.